This study examined (1) the incentive for achievement motivation of female and male Mexican American and Anglo American children and (2) the relationship between language behavior, as a possible indicator of acculturation, and modes of achievement motivation. A questionnaire type scale was developed to provide a viable assessment measure that is relevant for bicultural children who must learn to deal with the two sociocultural worlds of home and school. The Bicultural Achievement Motivation Scale (BAMS) contains 52 items and provides a general assessment of the motive to achieve. Four scales permit the assessment of the preferred mode of achievement; i.e. Achievement for Self and Achievement for Others within two achievement settings, Academic (competitive) and Home (non competitive). The scales permit assessment of the absolute as well as the relative strength of each motive and the identification of a bicultural child who exhibits a strong preference for both modes. In order to assess intracultural variability among Mexican American children, a Language Usage Index was developed and used as a possible indicator of degree of acculturation. All of the tests were developed in both English and Spanish versions. The subjects consisted of 480 fourth and sixth grade Mexican American and Anglo American students in three dispersed districts. (Author/JM)